Late Weichselian glacimarine depositional processes in the southern Skagerrak revealed by high-resolution seismic facies analysis

Thirty kilometres of high-resolution, seismic-reflection (boomer) data were collected in the Skagerrak area, between Norway, Sweden and Denmark, to re construct the seismic stratigraphy in an area of late Weichselian shelf-mar gin progradation. By the use of lap-out style, five depositional units, A-E , were recognised in the boomer profiles. No stratigraphic control was avai lable, but tentative correlation has been made on the basis of previous stu dies in the region. Unit A is interpreted as till. In unit B, the seismic f acies association includes shingled, mounded, oblique channel fill, and par allel-bedded reflection configurations, which are interpreted to have forme d in a channelled, proximal, pro-glacial environment. In unit C discrete mo unds and semi-continuous lensoid bodies with divergent channelled flow styl e constitute the facies association, and are interpreted predominantly as d ebris-flow deposits that accumulated in a distal pro-glacial environment. I n unit D, the facies association constitutes mounds and oblique in-fill bet ween mounds; positive relief and the distribution of facies shows that the deposits were laid down under the influence of a unidirectional current. Un its B-D are interpreted as late Weichselian in age. Unit E is interpreted a s the Holocene marine cover of laminated clay to fine sand. This seismic-st ratigraphic succession reveals a high-resolution record of late Weichselian deglaciation in this area. (C) 2001 Elsevier Science B.V. All rights reser ved.